FWIW, when I have had this problem it was due to a combination of circumstances that didn't have much to do with SM. I use Exim as my MTA, and under some circumstances it calls out immediately to try to deliver the message (i.e., while SM is still waiting for the final response code). If the callout fails, the send fails, Exim reports the reason to SM, and SM reports it to the user. On one occasion, an external site had some kind of illness and was giving a 354 response at the wrong time (I forget, but it might have been right after MAIL FROM:). SM was only showing this symptom when attempts were made to send to addressees on that site. (As it turns out, it was Yahoo, so the problem was showing up a lot.) The cure was to wait; they fixed themselves after a few hours. I mention this not only to pass along an amusing geek anecdote :-), but also because it was very difficult to track it down. Is there a pattern to the addresses when this happens? Check your MTA logs. ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ -- squirrelmail-users mailing list Posting Guidelines: http://www.squirrelmail.org/wiki/MailingListPostingGuidelines List Address: squirrelmail-users@xxxxxxxxxxxxxxxxxxxxx List Archives: http://news.gmane.org/thread.php?group=gmane.mail.squirrelmail.user List Archives: http://sourceforge.net/mailarchive/forum.php?forum_id=2995 List Info: https://lists.sourceforge.net/lists/listinfo/squirrelmail-users